Apparatus and methods are known for joining together sheets of thermoplastic film being used to feed a thermoforming apparatus. Taping splicing apparatus are known. Attempts have been made to butt weld thermoplastic sheets and films in an effort to continuously supply sheet to a thermoforming apparatus. However, no one has been successful in perfecting a process that is continuous and does not interrupt operation of the thermoforming apparatus. For example, U.S. Pat. Nos. 3,769,124; 3,834,971; 3,956,047; and 4,001,067 illustrate one attempt to splice sheets of thermoplastic film, but a lack of commercial success resulted due to shortcomings.